1. Field of the Invention
The present invention relates to a manufacturing method of a semiconductor device having a die stacking structure.
2. Description of the Related Art
An exponential increase in cost involved by miniaturization intensifies a possibility of a practical application of a three-dimensional multilayer of a circuit (a digital circuit, an analog circuit, a memory circuit, a sensor circuit, and others) that conventionally has a high cost. With such intensification, occurrence of a paradigm shift from miniaturization to realization of three-dimensionality is expected.
As effects of realization of three-dimensionality, 1) an increase in bandwidth, 2) a reduction in circuit area, 3) a reduction in wiring delay, and others can be considered. In particular, in order to realize 1), a high density of through substrate via is required. Further, in regard to 2), a density of through substrate via must be increased to efficiently perform a reduction.
As a method of increasing an electrode density in the vertical direction, a silicon substrate via has been actively proposed in recent years (see, e.g., Nikkei Electronics “Si Through Chip no Kozou Kakumei”, Oct. 10, 2005, pp. 81—99 [Nikkei Business Publications, Inc.]). In this technology, after an Si wafer is scraped to have a predetermined thickness, many through holes are formed at arbitrary positions of chips aligned on the wafer, and through substrate vias are formed in these holes by a method, e.g., plating. Stacking the chips (dies) each having this through substrate via enables realizing a three-dimensional circuit which connect the chips to each other at multiple points with a minimum distance.
However, a displacement margin must be assured to connect the through substrate vias of the plurality of dies to each other, and this obstructs a reduction in circuit area. Therefore, realizing a semiconductor device manufacturing method which can form connection through substrate via with a higher density than that in a conventional die stacking structure semiconductor device is demanded.